Document how the Device Lookup feature works

I've tried entering:
* The android "Serial" value (e.g. 4200dfa1e0329200)
* The device IMEI number (we log this manually from all devices as our own unique identifier as all our devices have GSM radios)
* The UUID of the device in Tracepot, as seen on the "Device History" page (e.g. 252eff61-2c0d-9105-8072-efa483223172, from this page: https://i.imgur.com/R3mciFU.png

All of the above show nothing but the red "Device not found." popup.

Any suggestions what I'm doing wrong, or how this feature is supposed to work?
It might be wise to add a snippet of text above the "Android Id" field in the Device Lookup popup, explaining what this ID is supposed to be and where to find it.